FISHERIES MAY BE DRIVING DECLINE

The study relied on what Price describes as a "biological treasure chest" of sockeye scales that have been collected since 1912, before the introduction of motorized fishing boats on the river.

By following genetic markers in the DNA extracted from those scales, the scientists were able to trace patterns of abundance in each of the 13 sockeye populations in the Skeena.

Previous research had suggested declines in seven of those 13 populations over the last 50 years. Price's team found that when they doubled that time frame, every population saw drops of between 56 and 99 per cent.

The researchers also developed a theory for why some populations have declined more sharply than others.

"What we found was those populations with historically the largest body size have declined the most, which suggests that fisheries selectivity is the most probable driver," Price said.

He said there are likely other contributing factors, but selective gill-netting for larger fish appears to be the best explanation.

The results suggest there's an urgent need for recovery plans for sockeye in the Skeena, as well as all salmon species across the province, Price argues.

"I'm hopeful this historical perspective provides us the information that can make more informed decisions in the future," he said.

This article, written by Bethany Lindsay, was originally published for CBC News.